Field of the Disclosure
The present disclosure, for example, relates to wireless communication systems, and more particularly to backhaul operations in a millimeter wave wireless communication system.
Description of Related Art
Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code-division multiple access (CDMA) systems, time-division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, and orthogonal frequency-division multiple access (OFDMA) systems.
By way of example, a wireless multiple-access communication system may include a number of base stations, each simultaneously supporting communication for multiple communication devices, otherwise known as user equipments (UEs). A base station may communicate with UEs on downlink channels (e.g., for transmissions from a base station to a UE) and uplink channels (e.g., for transmissions from a UE to a base station). A base station may communicate, either directly or indirectly with other base stations over backhaul links.
A base station, in a conventional communication system, typically enjoys a robust link to a network entity which coordinates aspects of the discovery and backhaul communications, e.g., the network entity provides timing information, cell identity, etc., for neighboring base stations to coordinate discovery and backhaul transmissions. Base stations operating in the millimeter wave (mmW) frequency ranges, e.g., 28 GHz, 40 GHz, 60 GHz, etc., may be associated with a reduced coverage area (e.g., a smaller geographic footprint, directional transmissions only, etc.), which may result in deployment of a much larger number of base stations to provide acceptable coverage areas. Such large-scale mmW base station deployments may impact the quality and availability of links to a network entity. For example, some mmW base stations may be deployed in areas with limited bandwidth links to a network entity and, in some examples, no links to a network entity. In a conventional cellular communication system, base stations may rely on a wired connection to a network entity and, therefore, may not typically perform discovery over the wireless medium. Such mmW base stations with limited or no links to a network entity still have a need to be able to discover other mmW base stations in order to perform backhaul operations. Moreover, such wireless discovery operations may provide a more beneficial deployment scheme for a dense population of mmW base stations, e.g., provide a lower cost and more feasible option to installing fiber optic communication lines to each mmW base station.